The invention relates generally to devices or apparatus for urging a ground rod, anchor rod, sign post, pipe, or other such rod-like members, into or out of the ground or other media through which such items are to be forcibly driven or retracted. More specifically, the invention relates to such devices or apparatus having a number of jaw members that grippingly engage the rod or other rod-like member and which preferably include means for imparting the driving or retracting force to the apparatus either manually or by use of power percussion tools or the like.
In the past ground rods, anchor rods, sign posts, and the like, have been driven into the ground or other similar medium by pounding on, or otherwise imparting impact blows on the end of the rod with a sledge hammer or other similar tool. Such methods have proven to be inconvenient and unsafe, especially where the rod or rod-like member is relatively long, because it was necessary for the worker imparting such impact blows to stand on a ladder or other elevated structure in order to be able to reach the top end of the rod with the hammer. In addition, such methods frequently required one or more additional workers to hold the rod in a stable lateral position during the pounding operation. Therefore, in the event of an inaccurate or errant impact blow, injury to the holder frequently resulted. In addition to being unsafe, such methods also made it difficult to avoid bending, nicking, or otherwise damaging the rod, sign post, or other rod-like member.
In light of the disadavntages of the manual pounding method described above, various devices and apparatuses for driving ground rods, sign posts, and the like, have been proposed but have frequently been found to be relatively cumbersome to use, inordinately complex and expensive to manufacture, relatively narrow in their ranges of applications and uses, or largely ineffectual in such driving or extracting operations without causing undue damage to the rod or other similar item. Examples of such prior devices and apparatuses are disclosed in U.S. Pat. Nos. 1,298,379; 2,145,420; 2,033,227; 2,330,360; 2,426,501; 2,693,086; 2,802,340; 3,034,588; 3,425,499; 3,454,113; 3,474,870; 3,499,497; 4,159,040; and British Pat. No. 1,486,581.
In accordance with the present invention, an apparatus is disclosed for driving or retracting ground rods or other rod-like members into or out of the ground or other substrata, or into or out of other media. The apparatus is relatively simple and inexpensive to manufacture, easy to use, and adaptable to both manual and power-operated force-applying devices. Generally speaking, an apparatus according to the present invention preferably includes a body portion, means for forcibly urging the body portion in either first and second longitudinal directions generally parallel to the rod or rod-like member being driven or extracted, at least a pair of jaw members slidably connected to the body portion in an opposed relationship for receiving the rod or other item to be driven therebetween, and abutment members fixed to the body portion for forcibly urging the jaw members laterally toward one another into a gripping engagement with the rod, thereby forcibly urging the jaw members and the rod or rod-like member in a driving first longitudinal direction. The body portion of the apparatus also preferably includes a guide mechanism for forcibly urging the jaw members laterally away from each other when the body portion is moved in a second opposite longitudinal direction in order to disengage the jaw members from the rod in order to remove or reposition the apparatus longitudinally on the rod. Additionally, the apparatus preferably includes an alignment mechanism for maintaining the jaw members at least in longitudinal alignment with one another as they are urged toward and away from the rod.
The body portion of the ground rod driving or extracting apparatus is preferably connectable to various adapter or anvil apparatus for use with either manual or powered force-applying devices and for interchangeable use with such devices in either rod-driving or rod-retracting operations.
Additional advantages, features, and objects of the present invention will become apparent from the following description and the appended claims taken in conjunction with the accompanying drawings.